by Neal Colgrass, Newser staff

by Neal Colgrass, Newser staff

That's how long the first human settlers stayed in Beringia - the region that once bridged Siberia and Alaska - before inhabiting North America about 15,000 years ago, according to a new scientific paper by University of Utah researchers.

Until now, scientists thought the vast tract of land was a treeless tundra unable to support much human life, but new drilling samples sourced from the Bering Sea and Alaskan bogs show insect and plant fossils, along with pollen, which suggest that shrubs, trees, and even animals may have lived there, National Geographic reports.

"It was an area where people could have had resources, lived, and persisted through the last glacial maximum in Beringia," says co-author Dennis O'Rourke, UNews reports.

The stopover theory also explains why Native American DNA differs from that of Asian ancestors: Settlers had time to develop their own genetic blueprint in isolation.

No evidence of human settlement has yet been found in Beringia, but O'Rourke attributes that to melting glaciers that submerged the lowland areas where he suspects the land favorable to habitation would have been located.

Still, he admits, his theory remains just that until archaeological evidence is discovered-which he thinks might be possible in "low-lying portions" of Alaska and Russia's eastern Chukotka. (In related news, an infant's DNA speaks to the origins of the first Americans.)

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